Inhibition of mitochondria responsible for the anti-apoptotic effects of melatonin during ischemia-reperfusion

Abstract

Abstract:Objective: To investigate a possible mechanism responsible for anti-apoptotic effects of melatonin and provide theoretical evidences for clinical therapy. Methods: Ischemia-reperfusion mediated neuronal cell injury model was constructed in cerebellar granule neurons (CGNs) by deprivation of glucose, serum and oxygen in media. After ischemia, melatonin was added to the test groups to reach differential concentration during reperfusion. DNA fragmentation, mitochondrial transmembrane potential, mitochondrial cytochrome c release and caspase-3 activity were observed after subjecting cerebellar granule neurons to oxygen-glucose deprivation (OGD). Results: The results showed that OGD induced typical cell apoptosis change, DNA ladder and apoptosis-related alterations in mitochondrial functions including depression of mitochondrial transmembrane potential (its maximal protection ratio was 73.26%) and release of cytochrome c (its maximal inhibition ratio was 42.52%) and the subsequent activation of caspase-3 (its maximal protection ratio was 59.32%) in cytoplasm. Melatonin reduced DNA damage and inhibited release of mitochondrial cytochrome c and activation of caspase-3. Melatonin can strongly prevent the OGD-induced loss of the mitochondria membrane potential. Conclusion: Our findings suggested that the direct inhibition of mitochondrial pathway might essentially contribute to its anti-apoptotic effects in neuronal ischemia-reperfusion.

Matrine induces apoptosis of human multiple myeloma cells via activation of the mitochondrial pathway

“…After matrine application, the mitochondrial-free cytosolic fraction and solubilized mitochondrial fraction were extracted from myeloma cells according to our previous study [13], and were then subjected to quantitation by employing a bicinchoninic acid protein concentration assay kit (Beyotime, Jiangsu, China). Cyt c protein was measured with a commercially available cyt c enzyme-linked immunosorbent assay (ELISA) kit (Calbiochem, San Diego, CA, USA) according to the manufacturer's instructions.…”

Anti-apoptotic protection afforded by cardioplegic celsior and histidine buffer solutions to hearts subjected to ischemia and ischemia/reperfusion

“…One of those small molecules that can be released is the cytochrome c [Krysko et al, 2001]. Cytosolic cytochrome c reacts with other proteins and activates pro‐caspase 3 triggering apoptosis [Han et al, 2006]. Insulin, which is present in HBS, is known to exert protection against I/R injury by inhibiting intracellular calcium transients [Yu et al, 2008], which may explain the overall higher protection against mitochondrial‐mediated apoptotic signaling in HBS‐preserved hearts.…”

Melatonin as a stabilizer of mitochondrial function: role in diseases and aging

“…Furthermore, melatonin reperfusion of ischemic hearts significantly lowered the degree of mitochondrial lipid peroxidation, prevented the loss in ETC function and the increase of H 2 O 2 production (Petrosillo et al, 2006), inhibited the formation of mPTP and related events, and preserved the content and integrity of CL molecules, suggesting a possible link between these processes (Petrosillo et al, 2009;Paradies et al, 2010). Focusing on the apoptotic pathway, it has been observed that the indole inhibits cytochrome C release and caspase 1 and 3 activation, thus preventing DNA fragmentation (Andrabi et al, 2004;Han et al, 2006;Wang et al, 2009). In other words, scientific evidence indicates that melatonin's effect during I/R is not only due to its direct/indirect antioxidant properties, but also due to its influence over mitochondrial homeostasis and dynamics (Srinivasan et al, 2010;Huang et al, 2013).…”

“…Similarly, most cerebral ischemia induced by various factors can be transiently reversed, although reperfusion produces further neuron damage (Han et al, 2006). After I/R, the oxidative stress, derived from impairment of ETC function (C-I and C-III) among other sources, is worsened by the concomitant depletion of endogenous antioxidants.…”